Field of the Invention
This invention relates in general to devices for sensing or detecting gases and in particular to a new and useful receptacle for the automatic connection of a gas sensor to a gas source.
The invention concerns a receptacle for the connecting of gas sensors to a measuring gas chamber provided with a gas inlet, into which extends a feeding line for the measured gas equipped with an operable shut-off element and at which gas inlet a sensor holder is attached, upon which a movable compression part touches that acts in the direction toward the gas inlet. A receptacle of this type is described in the EP-A 74 498.
The known receptacle has a measuring gas chamber with a gas inlet on which the gas sensor rests centrically with its gas-sensitive measuring surface. A holding clip is clamped as compression part on the back of the gas sensor, so that the gas-sensitive measuring surface rests on the opening of the measuring gas chamber. The measuring gas, which is fed into the measuring gas chamber for the purpose of calibration in the known case, is introduced into the measuring gas chamber from separate storage containers through feeding lines, after the feeding line from the gas source to the measuring gas chamber was opened by a separate switch.
In the case of the known instrument, care must be taken that the gas-sensitive measuring surface of the gas sensor is placed accurately on the gas inlet of the measuring gas chamber and a corresponding tension lever must be attached as compression part to the back of the gas sensor, to fix the gas sensor. In addition, the gas feeding line for the measuring gas must be opened with a separate manipulation. After the completion of the measurement, or the calibration, the gas sensor can be removed from the measuring gas chamber, but the additional task of shutting off the gas feeding line again must be remembered. When this shutting off is neglected, measuring gas continues to escape from the gas feeding line through the measuring gas to flow out uncontrolled, possible unnoticeable to the user.